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Thread: [GENERAL] Full text search with plain input

[GENERAL] Full text search with plain input

From
Havasvölgyi Ottó
Date:
Hi,

I would like to use PostgreSQL's FTS functionality.
The user would enter a search text, one or more words.
There is a suitable plainto_tsquery()  function, but it's to strict. It only matches if all words match. What is the best practice to make this kind of search more "forgiving", so that it matches (with less rank) even if one of its words match ?

Thanks,
Otto

Re: [GENERAL] Full text search with plain input

From
"David G. Johnston"
Date:
On Friday, May 4, 2018, Havasvölgyi Ottó <havasvolgyi.otto@gmail.com> wrote:
 so that it matches (with less rank) even if one of its words match ?

That seems to be what "ts_rank" provides.

David J.
 

Re: [GENERAL] Full text search with plain input

From
Havasvölgyi Ottó
Date:
Based on the docs, plainto_tsquery() creates tsquery with the & operator (https://www.postgresql.org/docs/10/static/functions-textsearch.html), so the @@ operator will not find partial matches. And this way I cannot calculate ts_rank for those partial matches.
Now I am thinking about splitting the input text myself to terms, then searching and ranking  the documents for each term. Finally summing the scores by document. This way the documents with more matching terms would get greater score.
Please anybody let me know if there is some better/easier solution for this.

Thanks,
Otto


2018-05-05 2:06 GMT+02:00 David G. Johnston <david.g.johnston@gmail.com>:
On Friday, May 4, 2018, Havasvölgyi Ottó <havasvolgyi.otto@gmail.com> wrote:
 so that it matches (with less rank) even if one of its words match ?

That seems to be what "ts_rank" provides.

David J.
 

Re: [GENERAL] Full text search with plain input

From
"David G. Johnston"
Date:
On Friday, May 4, 2018, Havasvölgyi Ottó <havasvolgyi.otto@gmail.com> wrote:

Now I am thinking about splitting the input text myself to terms, then searching and ranking  the documents for each term.

Maybe do: replace(input_text, ' ', ' | ')

David J.

Re: [GENERAL] Full text search with plain input

From
Havasvölgyi Ottó
Date:
Thank you David, I will do something similar.

2018-05-05 3:12 GMT+02:00 David G. Johnston <david.g.johnston@gmail.com>:
On Friday, May 4, 2018, Havasvölgyi Ottó <havasvolgyi.otto@gmail.com> wrote:

Now I am thinking about splitting the input text myself to terms, then searching and ranking  the documents for each term.

Maybe do: replace(input_text, ' ', ' | ')

David J.